Davis Adrian
MRC Institute of Hearing Research, University Park, Nottingham NG7 2RD, UK.
Int J Audiol. 2003 Jul;42 Suppl 2:2S39-52.
About 40% of 55-74-year-olds have an impairment in at least one ear of 25+ dB HL, and 27% have bilateral impairment at this level, with 11% being impaired bilaterally at 35+ dB HL. Only 6% currently use a hearing aid. The performance of a random sample of participants aged 55-74 years on speech-in-noise tasks shows that significant statistical benefit was obtained from bilateral amplification in over 20% of the population who do not currently use a hearing aid. The offer of a hearing aid to all those who exceeded a 25 dB HL criterion in the worse car was accepted and taken up by 40%, with 16% declining and the remainder being excluded for pathological and logistic reasons (e.g. hearing loss profile not suitable for aid). This is a very high rate of 71% acceptance. One in four fitted with the hearing aid showed a statistical advantage for hearing speech in noise in freefield (noise and speech from in front) with the hearing aid. Thus at least 10% of the population who do not currently use an aid would benefit substantially from a hearing aid in a quiet speech-in-noise environment. Those with poorer cognitive function show greater benefit overall and less disadvantage in very bad signal-to-noise environments. The overall pattern of results support screening and providing hearing aids to those who do not currently have an aid(s), and suggests that there would be considerable population benefit. At least two main questions for further research remain: (1) would bilateral aiding strategies give greater benefit; and (2) would different hearing aids and fitting strategies be more appropriate for people with differing 'cognitive task' loadings on phonological memory and lexical decision factors?
55至74岁的人群中，约40%的人至少有一只耳朵存在25分贝及以上的听力损失，27%的人双耳在此听力损失水平，其中11%的人双耳听力损失达35分贝及以上。目前只有6%的人使用助听器。对55至74岁参与者的随机样本进行的噪声环境下言语测试结果显示，超过20%目前未使用助听器的人群从双耳放大中获得了显著的统计学益处。向所有在较差耳朵中听力损失超过25分贝标准的人提供助听器，40%的人接受并使用了助听器，16%的人拒绝，其余的人因病理和后勤原因（如听力损失情况不适合佩戴助听器）被排除。这一接受率高达71%。四分之一佩戴助听器的人在自由声场（前方的噪声和言语）中佩戴助听器聆听噪声环境下的言语时显示出统计学优势。因此，至少10%目前未使用助听器的人群在安静的噪声环境下使用助听器将受益匪浅。认知功能较差的人总体受益更大，在非常恶劣的信噪比环境中劣势更小。结果的总体模式支持对目前未佩戴助听器的人进行筛查并提供助听器，这表明会给大量人群带来益处。至少还有两个主要问题有待进一步研究：（1）双耳助听策略是否会带来更大益处；（2）不同的助听器和验配策略是否更适合在语音记忆和词汇判断因素方面具有不同“认知任务”负荷的人群？
